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sawitt
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Joined: June 16, 2014
Posts: 65
Location: Brea, CA
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 Posted: Tue Feb 02, 2016 11:43 am Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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I'm going to go out and do the test that ashman40 suggests. I'm not sure if I'll be able to do it today or tomorrow. I'll report back what I find.
Thanks... |
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Dwayne1m
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Joined: December 31, 2011
Posts: 3538
Location: Pennsylvania
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| Posted: Thu Feb 04, 2016 5:08 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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I took a pic of my 78 engine so you can compare the position of the vacuum canister.
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sb001
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Joined: May 19, 2011
Posts: 10406
Location: NW Arkansas
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| Posted: Thu Feb 04, 2016 5:24 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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_________________
I'm the humblest guy on this board.
1969 autostick sedan, family owned since new
1600 SP engine
Solex 30 PICT 3 carburetor
Bosch 113905205AE autostick distributor |
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sawitt
Samba Member
Joined: June 16, 2014
Posts: 65
Location: Brea, CA
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| Posted: Fri Feb 05, 2016 12:12 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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| ashman40 wrote: |
To the OP, can I suggest you run the following test.. should only take 5min.
Rotate the crank until the rotor is pointing to the position of the #1 spark plug wire on the distributor cap.
Line up the TDC mark on the pulley with the case split if it is not perfectly lined up. If you don't have a TDC mark you can just use the timing notch.
Remove the #1/#2 valve cover (right side) and look at the #1 intake and exhaust valves. While you watch them, rock the crank pulley back and forth. The #1 valves/rocker arms should NOT move (cam lobes at TDC of compression stroke).
As a more positive confirmation... remove the #3/#4 valve cover and watch the #3 valves. Rock the crank pulley back and forth and BOTH #3 valves should move (cam lobes at TDC of exhaust stroke).
If the above test results in the expected action of the valves your rotor is indeed pointing at the #1 spark plug wire.
If on the other hand the valve motion is reversed (#1 valves are in motion), your rotor is actually pointing to the #3 spark plug wire.
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So was finally able to get out to the garage this morning. We pulled the left valve cover to look at #3 valves. So rotated the engine until the distributor rotor pointed to the index mark on the distributor housing. Rocked the engine back and forth watching the valves. First the #4 exhaust valve was moving, #3 was not moving. So we rotated the engine 360 deg. and lined up the rotor with the mark on the dist. housing. Now when rocking the engine back and forth both #3 valves were moving. So concluded that #1 was at TDC of the compression stroke.
There was a slight difference between the rotor lining up with the index mark on the distributor housing and the timing mark on the pulley lining up with the case split. Its about 5 deg or so, which I take to be the static timing that we set. The Bentley says the timing for a manual trans., F.I. engine is 5 deg ATDC. So it seems that this test indicates that the rotor is pointing to the #1 spark plug wire.
But, then we did the second test...
| Quote: |
If you want to check this... rotate the crank clockwise as you watch the #1 valves move. Watch the rocker as it opens and closes the #1 intake valve. Rotate the crank another 180-deg after the intake valve closes and you should be near TDC of the compression stroke for #1. Look at the crank pulley and make sure the TDC mark (or timing mark) is close to the case split. Look at the rotor, is it pointing to the #1 spark plug wire or the "pencil mark" you have on the distributor rim? |
My daughter was under the car looking at the #1 intake valve. Rotated the engine until that valve just closed. Rotated the engine another 180 deg. from that point. The crank pulley timing mark was about 30 deg. to the right (looking to the front of the car) of the case split line. The rotor was pointing about 30 deg. to the right of the index mark on the distributor housing. I quizzed her to make sure she was looking at the right valve, that it was closed, etc. We repeated the test with the same result and then did it again with me looking at the valve. She was right. So, I'm not sure what to do, maybe pull the distributor and look at the slot in the distributor drive shaft to see what it looks like. We were very careful when we put the dist. drive shaft, crankshaft and camshaft into the case when we started reassembling the engine and I think we did it right, but I can't explain these results. |
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busdaddy
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Joined: February 12, 2004
Posts: 51148
Location: Surrey B.C. Canada, but thinking of Ukraine
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| Posted: Fri Feb 05, 2016 1:39 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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| sawitt wrote: |
So was finally able to get out to the garage this morning. We pulled the left valve cover to look at #3 valves. So rotated the engine until the distributor rotor pointed to the index mark on the distributor housing. Rocked the engine back and forth watching the valves. First the #4 exhaust valve was moving, #3 was not moving. So we rotated the engine 360 deg. and lined up the rotor with the mark on the dist. housing. Now when rocking the engine back and forth both #3 valves were moving. So concluded that #1 was at TDC of the compression stroke.
There was a slight difference between the rotor lining up with the index mark on the distributor housing and the timing mark on the pulley lining up with the case split. Its about 5 deg or so, which I take to be the static timing that we set. The Bentley says the timing for a manual trans., F.I. engine is 5 deg ATDC. So it seems that this test indicates that the rotor is pointing to the #1 spark plug wire.. |
Please explain how you got it to line up once and then again 360 degrees later.
That 5ATDC only happens when the engine is running and making vacuum, static timing would be closer to 7.5 BTDC.
Stop looking at the mark in the distributor, the pulley is the one that counts. Since it seems there's still some confusion about the valves an alternate firing TDC test is stick your finger in the #1 sparkplug hole and feel for compression as you turn the engine (pulley CW from rear), when you feel air escaping slow down and stop when the pulley reaches TDC and attach whatever wire leads to #1 sparkplug to the hole in the cap that's over the rotor right now, then arrange the rest of the wires according to the new #1. The rotor may not be over the mark in the distributor but it'll run.
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Rust NEVER sleeps and stock never goes out of style.
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sawitt
Samba Member
Joined: June 16, 2014
Posts: 65
Location: Brea, CA
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| Posted: Fri Feb 05, 2016 5:35 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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So I went out and removed the distributor. The engine was rotated so that the crank pulley was at TDC. Our pulley is one of the ones that has the shallow dimple in the rear lip, which as I understand it indicates #1 TDC. It has a V cut to the left of the dimple which should be 5 deg. ATDC. I took a pic of the distributor drive shaft showing the slot and also the pulley. I think we've got the distributor driveshaft screwed up.
I colored the dimple with a silver sharpie (which is what I had nearby) to see it better. The dist. driveshaft slot is off by 10 to 15 deg. or so. It should be perpendicular to the engine case split line, which is vertical in that picture.
busdaddy: I can't get my finger down into the #1 sparkplug hole. I tried to use a drinking straw stuck down in the hole as an indicator but that didn't work too well either. The straw kept getting stuck on something and I was afraid of losing it in there. But I can reliably watch the #1 valves open and close as I turn the engine and it seems that when the #1 intake valve closes, the TDC dimple on the pulley is a little over 90 deg. to the left of the case split line. So I rotate the engine that amount until the dimple is on the case split line and that should be #1 TDC on the compression stroke. That's where I had it when I removed the distributor and took those pictures. |
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busdaddy
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Joined: February 12, 2004
Posts: 51148
Location: Surrey B.C. Canada, but thinking of Ukraine
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| Posted: Fri Feb 05, 2016 6:18 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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A pencil with a ball of tape or something else to reach down and plug the hole with will do if you have short fingers, that TDC mark is the correct one but it comes around twice for every one cam rotation, it could be #1 TDC but it could also be #3 TDC, te compression test removes all doubt. Another method is remove all the plugs except #1 and feel for the springy resistance on 1 stroke.
Don't go messing with any drives until you confirm you are at the correct TDC and not the #3 imposter.
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Rust NEVER sleeps and stock never goes out of style.
Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
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Cusser
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Joined: October 02, 2006
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Location: Hot Arizona
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sb001
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Joined: May 19, 2011
Posts: 10406
Location: NW Arkansas
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| Posted: Fri Feb 05, 2016 7:34 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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| sawitt wrote: |
I think we've got the distributor driveshaft screwed up.
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I agree, the distributor driveshaft position here is definitely wrong.
here is a guide for removing and reinstalling the distributor driveshaft:
http://www.tdreplica.com/VW%20Tech%20Pages/Distshaftremoval.htm
(Interestingly it looks like yours is positioned perfectly for a type 3!)
Just our of curiosity what is your distributor model #?
_________________
I'm the humblest guy on this board.
1969 autostick sedan, family owned since new
1600 SP engine
Solex 30 PICT 3 carburetor
Bosch 113905205AE autostick distributor |
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HRVW
Samba Member
Joined: May 01, 2011
Posts: 2531
Location: Rosarito, Mexico
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| Posted: Fri Feb 05, 2016 11:10 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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 Everybody makes the same mistake with the dist and the timing.
The dist drive gear has 12 teeth as such that many spots for #1 or #3 to be pointing. The DENT in the pully would be TDC at the case seam (not exactly correct but close enough) for any novice.
With that DENT at the seam and the dist installed the rotor will be pointing towards #1 or #3 PERIOD....12 different spots.
FORGET that slot/notch in the dist body (if any) as that was the original Factory setting on assembly and has been changed zillions of times over the decades on rebuilds.
Have the plug wires and the cap directly over the rotor 1-4-3-2 order.
Try to start the engine. If the FI is all correct the engine should fire right up. If it pops out the exhaust or up thru air filter then exchange #1/3 and 2/4 wires and try again ....saves looking at the valves opening or closing.
(VW mechanic/engine builder/parts house owner of 28 yrs) |
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HRVW
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Joined: May 01, 2011
Posts: 2531
Location: Rosarito, Mexico
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| Posted: Fri Feb 05, 2016 11:10 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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Everybody makes the same mistake with the dist and the timing.
The dist drive gear has 12 teeth as such that many spots for #1 or #3 to be pointing. The DENT in the pully would be TDC at the case seam (not exactly correct but close enough) for any novice.
With that DENT at the seam and the dist installed the rotor will be pointing towards #1 or #3 PERIOD....12 different spots.
FORGET that slot/notch in the dist body (if any) as that was the original Factory setting on assembly and has been changed zillions of times over the decades on rebuilds.
Have the plug wires and the cap directly over the rotor 1-4-3-2 order.
Try to start the engine. If the FI is all correct the engine should fire right up. If it pops out the exhaust or up thru air filter then exchange #1/3 and 2/4 wires and try again ....saves looking at the valves opening or closing.
(VW mechanic/engine builder/parts house owner of 28 yrs) |
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Cusser
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Joined: October 02, 2006
Posts: 31379
Location: Hot Arizona
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| Posted: Sat Feb 06, 2016 9:09 am Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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I still say easiest is to line the pulley dent with the case seam, pull off right valve cover and see if both #1 valves are fully closed, and if not rotate engine one full turn so they are, then see if the distributor rotor is underneath the spark wire that goes to #1 cylinder, and go from there.
I may be helping a new member close by with just this today.
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1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297 |
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sawitt
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Joined: June 16, 2014
Posts: 65
Location: Brea, CA
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| Posted: Sat Feb 06, 2016 9:15 am Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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| The distributor is a Bosch 0 231 176 044, which according to the data I can find is the correct one for this year of car. |
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sawitt
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Joined: June 16, 2014
Posts: 65
Location: Brea, CA
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| Posted: Sat Feb 06, 2016 9:35 am Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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| I agree about using the valves and the pulley dent to get TDC. I can lay down with a ratchet on the alternator pulley and turn the engine pretty easily while watching the valves. After trying a couple of different ways yesterday that seemed to be the easiest for me. We did the straw thing a month or so ago and it worked but yesterday the darn thing kept getting stuck for some reason. And on the FI engines, there is a lot of crap down by the spark plug holes: fuel lines, injector connections, etc. |
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ashman40
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Joined: February 16, 2007
Posts: 15985
Location: North Florida, USA
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| Posted: Sat Feb 06, 2016 5:33 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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| sawitt wrote: |
| We pulled the left valve cover to look at #3 valves. So rotated the engine until the distributor rotor pointed to the index mark on the distributor housing. Rocked the engine back and forth watching the valves. First the #4 exhaust valve was moving, #3 was not moving. |
With the crank at TDC and #3 valves not moving... rotor is pointing to #3 spark plug wire position.
| sawitt wrote: |
| So we rotated the engine 360 deg. and lined up the rotor with the mark on the dist. housing. Now when rocking the engine back and forth both #3 valves were moving. So concluded that #1 was at TDC of the compression stroke. |
Where was the rotor pointing at this point? This should be where the #1 spark plug is on the distributor cap.
Do you have two marks on the distributor housing? The big square notch (10-o'clock in the below pic) is the distributor cap index slot so the cap can only go on one way. This big slot varies depending on the distributor model. The small notch/nick along the rim (2-o'clock) is the #1 plug wire position mark ("permanent pencil mark").
{This distributor (pic I found in the gallary) appears to be rotated a little cw from where I would normally expect it to be}
| sawitt wrote: |
| There was a slight difference between the rotor lining up with the index mark on the distributor housing and the timing mark on the pulley lining up with the case split. Its about 5 deg or so, which I take to be the static timing that we set. The Bentley says the timing for a manual trans., F.I. engine is 5 deg ATDC. So it seems that this test indicates that the rotor is pointing to the #1 spark plug wire. |
This small notch is NOT a TDC mark or a timing mark. It is not precise enough. It is just a mark so you can remember where the #1 spark plug wire goes when installing wires around the cap, nothing more. It is not critical that the rotor point exactly at this mark when at TDC or 5ATDC. Remember that the rotor position will change as the engine RPMs change. This is why the tip is wide. As long as the spark plug wire is closest to the rotor tip the spark will jump there.
| sawitt wrote: |
But, then we did the second test...
My daughter was under the car looking at the #1 intake valve. Rotated the engine until that valve just closed. Rotated the engine another 180 deg. from that point. The crank pulley timing mark was about 30 deg. to the right (looking to the front of the car) of the case split line. The rotor was pointing about 30 deg. to the right of the index mark on the distributor housing. |
I'm sorry if I was generalizing and not being specific. Instead of rotating the engine 180-deg after the intake closes I should have said rotate it cw until the crank pulley TDC mark next lines up with the case split. It should happen within the next 180-deg of crank rotation. If your intake valve is fully closing much after BDC then the TDC mark will come around before another 180-deg of crank rotation.
Since you have a way to rotate the engine while watching the #1 rocker arms confirm the following as you rotate the crank cw through a full 720deg (4-stroke cycle):
#1 intake valve starts to open around the point where the TDC mark passes the case split (end of exhaust stroke). The rotor should be pointing to the #3 spark plug position on the distributor.
#1 intake valve closes around BDC (bottom of intake stroke)
At the top of the next stroke (end of compression stroke) the crank pulley TDC mark lines up with the case split. This is when the rotor should be pointing to the #1 spark plug position on the distributor.
At the bottom of the stroke (end of power stroke) the exhaust valve starts to open.
At the top of the stroke (end of exhaust stroke) the exhaust is closing and the intake is opening. This should be 720deg (two rotations) from where you started.
It is normal for the valve to open slightly early (before the top of bottom of the stroke) and close slightly late (more than 180-deg of crank rotation). But if a valve opens late and closes late (or opens early and closes early) then the cam may be indexed incorrectly.
It appears your distributor drive shaft is about 30-deg off from where it should be. This would indicate the gear of off by 1-tooth. It also explains why your vacuum can is rotated slightly ccw from where most are used to it being.
It is possible to pull; rotate and re-insert the gear by one tooth and it should be very close to perpendicular. Just realize that 1-tooth means a 30-deg change in the drive gear position. If your gear was off by only 15-deg then rotating the gear one tooth would make it off by 15-deg in the other direction. So it is only worth re-indexing the gear if it is off by 30-deg or more.
_________________
AshMan40
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'67 Beetle #1 {project car that never made it to the road  }
'75 Beetle 1200LS (RHD Japan model) {junked due to frame rot}
'67 Beetle #2 {2019 project car - Wish me luck!} |
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sawitt
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Joined: June 16, 2014
Posts: 65
Location: Brea, CA
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| Posted: Sat Feb 06, 2016 7:59 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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| ashman40 wrote: |
It appears your distributor drive shaft is about 30-deg off from where it should be. This would indicate the gear of off by 1-tooth. It also explains why your vacuum can is rotated slightly ccw from where most are used to it being.
It is possible to pull; rotate and re-insert the gear by one tooth and it should be very close to perpendicular. Just realize that 1-tooth means a 30-deg change in the drive gear position. If your gear was off by only 15-deg then rotating the gear one tooth would make it off by 15-deg in the other direction. So it is only worth re-indexing the gear if it is off by 30-deg or more. |
Yes the distributor driveshaft was off about 30 deg., which should be one gear tooth. So I was able to pull the driveshaft up and rotate it CW 20-30 deg. and drop it back down. Now the driveshaft is fundamentally perpendicular to the case split line. Put the distributor back on, statically timed it and tried to restart. Didn't start. I really thought that I'd fixed a problem with the distributor though. So we poured a little gas into the black rubber boot upstream from the throttle body and the engine ran for 30 - 40 sec. I believe we fixed the ignition problem and now have a fuel problem to figure out.
We pulled out the #3/#4 fuel injectors and cranked the engine to see if they were squirting fuel. #3 did but #4 did not. It was getting late in the day so we didn't try the #1/#2 injectors. There's a good FI troubleshooting section in the Bentley, some of which we've already done. So I think we need to go in that direction.
One thing that troubles me is the fact that for a couple of weeks we had the ground connections from the ECU tied to B+ on the alternator instead of the ground connection. We may have fried the ECU. One can't really test the ECU, everything else is checked and if it is all ok, then replace the ECU.
Tomorrow I plan to start at the injectors and check voltages and resistances of the circuit back to the ECU and double relay. Also see if we can see the #1/#2 injectors squirting fuel.
My daughter knows another student who goes to the same university as her who has a beetle almost exactly like hers, a Super FI, maybe a '78. His car is running, he drives it to school, and she's going to try to get in touch with him and see if he'll mind trying our ECU in his car. That would seem to be a way to 'test' it.
I'd like to sincerely thank everyone who helped us on this. You taught us some things we need to know and caused us to remember some things we should've remembered. We sure appreciate you taking the time to share your hard-earned wisdom with us. Thanks... |
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Dwayne1m
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Posts: 3538
Location: Pennsylvania
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| Posted: Sat Feb 06, 2016 9:24 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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| Another thing to look at is the injector resister pack and make sure none of the wires are broke. |
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marc330
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Joined: May 30, 2015
Posts: 83
Location: Cambridge On
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| Posted: Sat Feb 20, 2016 4:43 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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This all seems very familier to me!!
I rebuilt my 79 beetle last year and had 6 months of issues, with everyone on this site helping I finally got it fixed.
I would agree with the other posts that it is your intallation of the distributor, you probably have it installed with your #3 clyinder at TBC instead of your # 1 ..quick check would for that is to switch your wires on the distributor cap--1 with 3 and 2 with 4 and see if it starts.
I hope you get it going or have already! if your still having issues send me a PM, I'm not an expert but I recently went through hell getting mine going that I could probably help with your troublesooting..hope you dont have any vacuum leaks ! |
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marc330
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Posts: 83
Location: Cambridge On
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| Posted: Sat Feb 20, 2016 4:48 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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Didnt see your last post !! my bad!
Your probably already past this point but if you hae the #3 and #4 injectors out and #4 isn't spraying just switch the wireing harness plugs to see if its the injector or electrical |
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sawitt
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Joined: June 16, 2014
Posts: 65
Location: Brea, CA
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| Posted: Sat Feb 20, 2016 9:19 pm Post subject: Re: 78 Super Won't Start After Engine Rebuild |
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| marc330 wrote: |
Didnt see your last post !! my bad!
Your probably already past this point but if you hae the #3 and #4 injectors out and #4 isn't spraying just switch the wireing harness plugs to see if its the injector or electrical |
We've made some progress in troubleshooting this. I dumped a little gas in the black rubber boot between the intake air sensor and the throttle body and the car started and ran for 30-40 sec. Did it twice. So, we've got a fuel problem. So, although I thought our fuel injectors were all good because we had them rebuilt by a very reputable guy, we pulled all the injectors from the intake manifold so we could actually see them squirting fuel. Much to my surprise only the #3 injector was squirting fuel. We switched electrical connections with no change, plus tested all 4 of the injector connectors with a test light and they were getting voltage. We had also checked the resistor pack too. Crap! So I bought a new injector from The Bus Depot, which was on sale. We also replaced all the electrical connectors to the fuel injectors because the corners on the plastic shells were starting to break and a couple of them weren't positively being retained on the injectors. The new injector worked normally and we tested all 4 of the new injector connectors we installed on the 2 working injectors we have. So I have 2 more injectors on order and I really think that we've found our problem. But I've thought that before... So, crossing our fingers. |
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